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प्रश्न
A converging lens has a focal length of 50 cm. The power of this lens is:
विकल्प
+0.2D
−2.0D
+2.0D
−0.2D
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उत्तर
+2.0 D
Power `=1/"focal length"=1/0.5=+2D`
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संबंधित प्रश्न
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Fill in the following blank with suitable words :
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Mohan obtained a sharp inverted image of a distant tree on the screen placed behind the lens. He then moved the screen and tried to look through the lens in the direction of the object. He would see:
(1) a blurred image on the wall of the laboratory.
(2) an erect image of the tree on the lens.
(3) no image as the screen has been removed
(4) an inverted image of the tree at the focus of the lens.
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Assertion and reasoning type
- Assertion: Myopia is due to the increase in the converging power of eye lens.
- Reason: Myopia can be corrected with the help of concave lens.
An object is placed in front of a converging lens. Obtain the conditions under which the magnification produced by the lens is
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